Drive train problems

m3trackboy

I’ve got a drive chain problem which I can’t see an obvious cause.
When I pedal hard there are clonking noises and juddering through the pedals, it feels like the chain is slipping on the gears, if I brake and try to pedal it will do it in all the gears on the back cassette.
I changed the cassette and chain but still it happens. If I put it on a stand the shift is perfect and there’s no way I can replicate the problem. I have noticed the hanger for the derailleur is very slightly out of line but the “drive side” is spot on.
I suspect the front gear rings but don’t want to start replacing bits adhoc. Is there any way I can eliminate parts or do I just replace bits till it’s cured.
Any help gratefully received

owenlars

Could be bottom bracket. Is the noise regular every turn of the pedals? You can check by looking for play in the cranks by pulling them to and fro from side to side. Any play and the bearings are either shot or loose. It may also be coming from the pedals, try tightening them. The problem with noises is that it is often very difficult to find where they come from.

Try this. http://sheldonbrown.com/creaks.html

YeehaaMcgee

look down at the chain whilst putting the power down, you may be able to see the chain jumping.
Also, try locking the rear wheel, balancing on the bike and putting everything you've got through the pedals - if it skips then, then it may be the freehub.

m3trackboy

Thanks for the reply's i'm pretty sure it's BB, as it's 3 years old I'm going to change from Race Face to XT, nothing wrong with the RF but heard they had gone under and as the rest of the drive train is Shimano might as well change the front end to match

Thanks for the help

YeehaaMcgee

For what it's worth, Hope bottom brackets are actually very well made. They're just about the only bit of hope gear I'd choose.
Damned expensive though, so admittedly I generally just buy cheaper Shimano ones, and treat them as a consumable item